Stefan Monnier writes:
>> 1. ECB is now part of CEDET, which in turn is installed in Emacs, so it can
>> be removed from the list of packages to install (search for "ECB").
>
> AFAICT ECB is not yet in Emacs.  Maybe it's just a matter of sync'ing
> with the upstream CEDET, in which case, I suggest we try and sync ASAP
> and then we can remove this entry indeed.

No, ECB is not part of CEDET.